Book box desk



Jan. 2, 1962 R. G. MoHR ETAL BOOK BOX DESK 2 Sheets-Sheet 1 Filed June5, 1959 INVENTORS.

Jan. 2, 1962 R. G. MOHR x-.TAL 3,015,531

BooK Box' DESK Filed June 5, 1959 f1 2 Sheets-Sheet 2 ZZ H-/ 16 r11/uw l/fww Eil/VW] 2 5am; JWM

United States Patent C 3,015,531 BGOK BOX DESK e Robert G. Mohr andRichard J. Lappin, Kalamazoo,

Mich., assignors to Brunswick Corporation, a corporation of DelawareFiled June 5, 1959, Ser. No. 818,345 2 Claims. (Cl. S12-316) Thisinvention relates to furniture, and more particularly to a book box deskintended principally for use in school rooms, though its utility is notso limited.

lt is a general object of the invention to provide a new and improvedbook box desk.

A more specific object is to provide a new and improved desk of the typedescribed including a book box having a top opening, a book box coverpivotable on the box over the opening and providing a desk top, and ayieldable torque means urging the cover toward open position with lessforce the closing force of the cover when closed and with greater forcethan the closing force of the cover when open to thereby hold the coverin open position.

Another object is to provide a new and improved book box desk of thetype described in the preceding paragraph including a friction deviceexerting a retarding effect on the cover which is greater than theclosing force of the cover to prevent the cover slamming closed.

Other objects and advantages will become readily apparent from thefollowing detailed description taken in connection with the accompanyingdrawings, in which:

FIG. 1 is a top plan view of a book box desk embodying the principles ofthe present invention;

FIG. 2 is a fragmentary side elevational view of the desk illustrated inFIG. l;

FlG. 3 is a fragmentary enlarged plan view, with the cover removed,taken at about the line 3-3 of FlG. 2;

FIG. 4 is a fragmentary sectional view, taken at about the line 4 4 ofFIG. 3;

PEG. 5 is a fragmentary sectional view taken at about the line 5-5 ofFlG. 4;

HG. 6 is a fragmentary sectional view takcn at about the line 6-6 ofFIG. 5;

FIG. 7 is a fragmentary sectional view, partly broken away, taken atabout the line 7-'7 of FlG. 3;

FIG. 8 is a fragmentary sectional View taken at about the line 8-8 ofFlG. 7; and

FG. 9 is a graph including a straight line curve illustra ing thevarying force of the yieldable torque device and another curveillustrating the varying closing force of the cover.

While an illustrative embodiment of the invention is shown in thedrawings and will be described in detail herein, the invention issusceptible of embodiment in many different forms, and it should beunderstood that the present disclosure is to be considered as anexempliiication of the principles of the invention and is not intendedto limit the invention to the embodiment illustrated. The scope of theinvention will be pointed'out in the appended claims.

Referring now to the drawings in more detail, a desk constructedaccording to the principles of the present invention preferably includesa book box 1li having a bottom Wall 11 (PIG, 3), side walls 12, a frontWall 13 and a rear wall 14. The box 1li is open at the top, and amovable book box cover 16 overlies the top opening when the cover is inclosed position. The cover 16 is hinged to the rear wall 14 of the bookbox by conventional hinge means such as that illustrated at 17 and 1S,so that the cover is movable from a closed position illustrated in thedrawings to a forwardly and upwardly inclined fully open position (notshown) which exposes the interior of the book box for ready access.

Patented Jan. 2, 1962 ice Usually, the book box 10 with the cover 16 issupported at a suitable elevation by a suitable leg structure such asthat illustrated in part at 2l) in FIG. 2.

In order to control movement of the book box cover, and particularly theclosing movement of the cover to prevent its weight and resultantclosing force from slamming the cover shut, a friction device isprovided which exerts a minimum, substantially insignificant effect onopening movement but which exerts a substantial retarding eect onclosing movement, and which preferably is greater than the closing forceof the cover to thereby hold the cover in partially open positions andrequiring but a light manual pressure to close the cover.

The friction device, generally designated 22 is best illustrated inFIGS. 3-6, and includes a rst supporting bracket including a centralportion 23, an end portion 24 welded or otherwise suitably secured tothe adjacent side wall 12, and an opposite end portion 25 whichterminates in a laterally turned ange 26 which is welded or otherwisesuitably secured to the rear wall 14. This bracket may be referred to asan inner support, and its central portion 23 is formed with acirculardepression as at 2S which receives a circular friction element 29,preferably comprising a disc of leather, one surface of which is adaptedVto continuously engage a depending arm 31 secured to the underside ofthe cover 17 as by means of a laterally turned flange portion 32 securedby screws or the like as at 33.

As seen best in FlGS. 3, 4 and 5, a second supporting bracket 35 isprovided and this may be referred to as an outer bracket as itsubstantially encloses the inner bracket as well as the arm 31 dependingfrom the cover 16. The outer, covering bracket 35 may be supported as bymeans of bolts or screws as at 37 and 38 attaching the outer bracketrespectively to the portions 25 and 23 of the inner bracket. rlhe outerbracket is formed with a generally rectangularly shaped depression as at40 which has a bottom wall 41 inclined relative to the path of thedepending arm 31. The bracket 40 is adapted to receive a second frictionelement in the form of a block 43 of powdered iron or the like whichcarries a friction insert in the form of a generally rectangular pieceof leather 44 adapted to oppose the leather element 29 and engage theopposite surface of the depending arm 31.

As will be readily understood, particularly on viewing FlG. 5, when thebook box cover 16 is pivoted upwardly from a closed position toward anopen position, the depending plate-like arm 31 moves upwardly with thecover, and due to its engagement with the leather element 44 causes theblock 43 to tend to rise in the pocket 40. Due to the inclination of thebottom wall 41 relative to the path of the arm 3l, such upward movementof the block 43 reduces the frictional drag on the arm 31 to a nominalvalue which exerts little or no signicant retarding effect on themovement of the cover.

On the other hand, when the book box cover is moved from an openposition toward the closed position the downward movement of the arm 3l,frictionally engaging the leather disc 29 andthe leather element 44,induces movement of the block 43 downwardly. At this time, due to theinclination of the wall 41 the leather element 44 is crowded against thearm 31 and exerts a substantially increased retarding effect on themovement of the cover which is sufficient to hold the cover in an openposition. That is, the retarding effect of the friction device exceedsthe closing force of the cover due to its mounting.

The retarding effect of the friction device may be adjusted by adjustingthe bolt means 3S which has the effect of drawing the outer bracket 35closer to the inner bracket portion 23 thereby crowding the leatherelements 28 and 44 more closely together.

The amount that the cover may be opened is limited by means of ahook-shaped end portion 46 (FIG. 4) on the lower end of arm 41 whichfunctions as a stop engageable with the shaft of the bolt means 33, asbest seen at 47 in FIG. 3, which functions-as a stationary stop limitingmovement of the movable abutment 46. ln a preferred embodiment, thecover member is pivotable through an angle of about 50 from the closedportion shown, whereupon the abutment d6 engages the stop 47.

AS best seen in FIGS. 3, 7 and 8, according tothe present invention thedesk is provided with a yieldable torque means acting on the book boxcover and exerting a force tending to open the cover but which force isless than the closing force of the cover when closed and which exceedsthe closing force of the cover when open. Thus, the cover remains closedwhen closed and remains open when open. Intermediate these two extremes,the opening force of the torsion device equals the closing force of thedoor, so that the cover may be manually moved from 'the closed positionillustrated to `an intermediate position whereupon the torsion devicewill cause continued movement of the cover from the intermediateposition to the fully open position.

The torsion device, generaly designated 50, includes an elongate torsionbar having a yieldably twistable intermediate portion 51 of a lengthsomewhat less than the Width of the book box, and having at one end anarm 52 adapted for attachment to the book box, and having at the otherend an arm S3 engageable with the underside of the book Vbox cover 16,preferably through the medium of the laterally turned dlange 32 of thedepending friction `arm 31 (FIGS. 4 and 5).

The torsion bar is disposed primarily in the book box and is mountedthereon by means of a forwardly and downwardly turned integral flange 55at the upper edge of the rear wall 14, a somewhat similar forwardly anddownwardly turned flange as at 56 at the upper edge of the rear wall 14adjacent the torque arm 52, and a forwardly and upwardly turned flange57 at the upper edge of the rear wall 14 adjacent the torque arm 53.These flange means, engaging Vthe intermediate portion l of the torquebar centrally of its length and adjacent its opposite ends, hold thesame captive in an operative position. This independent mounting of thetorque bar enables independent design of the bar to meet its operationalrequirements, and holds the torsion bar free to function in the propermanner.

The torque arm 52 is adjustably secured to the book vbox by means of amounting bracket best illustrated in FIGS. 7 and 8, and including a angeportion 60 welded 'or otherwise suitably secured to the adjacent sidewall V12 of the book box, a central plate portion 61 and spacedange-like lugs 62. The central plate portion 61 is formed with aplurality of laterally and upwardly extending and opening notches orslots as at 64, six as illusv'trated, and each of these is adapted toreceive the torque larm 52 so that the latter may be positioned in anyof the notches to thereby vary the force exerted by the torsion bar.

.It will be understood that with the oppositevtorque varm 53 urging thecover upwardly, the torque arm 52 reacts downwardly in the notches 64,and the higher the torque arm 52 is positioned on the plate 61 thegreater 4the-force exerted by the torsion bar. This construction'enables use of the same torsion bar with covers of dif- `ferentweights. The torque arm 52 and the mounting bracket securing same to thebook box are substantially enclosed by a Vcover 66 which is secured inposition by bolt or screw means as at 67 attached to the lugs 62.

Referring to FIG. 9, the graph illustrates the varying closing force ofthe book box cover in a curve designated A and the varying force of thetorsion bar in the straight line B, in inch-pounds on the ordinateversus the angular position of the door on the abscissa. It is obvious,of course, that the closing force of the cover varies from a maximumvalue when the cover is near a horizontal closed position to a minimumvalue when the cover would be manually raised, with only a light liftingpressure necessary, from the closed position to about a 45 positionwhereupon the torsion oar would lift the cover to thetfully openposition and maintain the same open. In the range from 6 to 45, wherethe closing force of the cover exceeds the opening force of the torsiondevice, the cover will be held in open positions by the friction'device22.

We claim:

l. A book box desk, comprising a book box having a top opening, a bookbox cover on the book box, hinge means mounting the cover on the rear ofthe book box for pivotal movement between a rst position closing thebook box and a second inclined position exposing the interior of thebook box, an arm depending from the cover, a friction device mounted onthe book box engageable with said arm, movable to a first position inresponse to arm movement in an opening direction to exert a minimumsubstantially insignicant frictional drag on the arm during openingmovement of the cover, and movable to a second position in response toarm movement in a closing direction to exert an increased frictionaldrag on the arm on closing movement of the cover to reduce the tendencyof the cover to slam closed, and a resiliently yieldable means actingbetween the book box and the cover urging the cover toward open positionwith less forceV than the combined closing force of the cover andretarding eiect of the friction device, in the opening direction, whenthe cover is in any position between the iirst, closed position and athird position intermediate the first and second positions, theretarding effect of the friction device, in the closing direction, beingat least equal to the net closing force of the cover when the cover isin any position between the first' position and the third position,whereby the cover may be manually opened to any position between thetrst position and the third position and remain there, said yieldablemeans urging the cover toward open position with greater force than theclosing torce of the cover and the retarding edect of the frictiondevice, in the opening direction, when the cover is in any positionbetween said second, open position and said third position, whereby thecover may be opened by said yieldable means from the third position tothe second position.

2. A book box desk, comprising a book box having a rear wall and a topopening, a movable cover on the top of said book box, hinge meansmounting the cover at the upper edge of the rear wall for pivotalmovement between a first position closing the book box and a secondinclined position exposing the interior of the book box, an armdepending from the cover, a friction device mounted on the book Abox,engageable with said arm, movable to a rst position in response to armmovement in an opening direction to exert a minimum substantiallyinsignificant frictional drag on the arm during opening movement of thecover, and movable to a second position in response to arm movement in aclosing direction to exert an increased frictional drag on the arm onclosing movement of the cover to reduce the tendency of the cover toslam closed, a torsion bar having an intermediate yieldably twistableportion mounted on the book box at the rear edge thereof, an arm at oneend secured to the book boxand an arm at the other end engaging theunderside of the cover, urging the cover toward open position with lessforce than the combined closing force of the cover and retarding eiectof the friction device when the cover is in any position between thefirst, closed second positions, the retarding etlect of the frictiondevice being at least equal to the net closing force of the cover whenthe cover is at any position between the rst, closed position and saidthird position, whereby the cover may be manually opened to any positionbetween the iirst position and the third position and remain there, saidtorsion bar urging the cover toward open position with greater forcethan the closing force of the cover and the retarding eiect of thefriction device when the cover is in any position between said second,open position and said third position whereby the cover may be opened bysaid torsion bar from the third position to the second position, andmeans mounting said torsion bar intermediate portion on the book boxcomprising, forwardly and downwardly turned ange means at the upper edgeof the rear wall of the book box centrally of the length of saidintermediate portion and adjacent said iirst mentioned torsion bar arm,and forwardly and upwardly turned flange means at the upper edge of saidrear wall adjacent the second mentioned torsion bar arm, said ange meansholding said intermediate portion captive in operative position.

References Cited in the iile of this patent UNITED STATES PATENTS822,555 Rogers June 5, 1906 2,213,319 Lickteig Sept. 3, 1940 2,602,957Anderson July 15, 1952 2,831,238 Mohr Apr. 22, 1958 2,871,505 Clark Feb.3, 1959 2,894,277 Bogater July 14, 1959

